This will allow later more gpu candidates.
Note: This is an unfinished work, we keep the previous behavior for now
To finish this, all algos solutions should be migrated and submitted nonces attributes stored.
Its required to handle the different share diff per nonce and fix the possible solved count error (if 1/2 nonces is solved).
optimized for the 9xx and more recent, same results on the 750 Ti
+ restore second nonce support not present in nicehash published version
Better on linux at least...
Tanguy Pruvot